1. Field of the Invention
This invention relates to an agricultural machine for harvesting crop, comprising a frame provided with a tongue for hitching to a tractor, and carrying wheels which move over the ground alongside the tractor during the work, the frame carrying a cutting device and a conditioning and/or throwing device, as well as adjusting deflectors located on its back side.
2. Background of the Related Art
A known machine of this type can occupy a work position in which the cutting device and conditioning and throwing device are perpendicular to the direction of advance and the deflectors are adjusted so that the crop is gathered and falls on the ground approximately on the right side--viewed in the direction of advance --of the width of the cutting pass.
At the next passage, the position of the deflectors is modified so that the gathered crop falls on the ground approximately on the left side of the width of the cutting pass.
With such an arrangement, the windrows formed in two successive passages are brought together. This arrangement, applied to a machine with great work width, still does not make it possible to gather two windrows, so they form only one windrow of a reduced width, able to be gathered with standard pick-ups of the most up-to-date forage harvesters.
On the other hand, on this machine, the frame with the cutting device and conditioning and/or acceleration device is farther away from the tractor during the second passage to keep its wheels from crushing the hay cut during the first passage. Consequently, the tractor driver must modify his guide marks at each passage.
Further, when the machine is farther away from the tractor, it has more of a tendency to shift toward the back side of the tractor. For this reason, the work width is very irregular and the driver must constantly correct the path.
Finally, when the machine is in the position farthest from the axis of the tractor, its center of gravity is close to the front side of the support triangle defined by its two carrying wheels and the point of hitching the tongue to the tractor. The stability of the machine consequently is precarious in this position.